This is probably the most common issue we are seeing from our customers lately. The 800 number pop up and the fake “Microsoft” technicians calling your home. The call me once a month and next time they call I will make a video of my interaction with these dangerous scammers. In the meantime, here is a video of the 800 number pop up in action and how you can close it. DO NOT CALL THE NUMBER! If one of the scammers calls your house, hang up.
I have seen the damage these people can inflict. The last customer that I worked with called the number, let them in the computer and then they demanded $250 to “fix” the problem. She said, “no thanks” and they locked her out of her computer with a registry password. Then kept calling back every day or two to ask for the $250 to tell her the password.